Enables keystone-enabled Quantum in devstack.
Enables keystone-enabled Quantum in devstack.

Fixes bug 1028075.

Whether keystone is enabled for Quantum is determined according to Q_AUTH_STRATEGY.
* 'keystone' (default): Enables authN with keystone for Quantum
* 'noauth': No authN used by Quantum.

Change-Id: Icfc77089e085b43e97601869d9c61c9f4da1164b

deepakselvaraj/devstack,olivierlemasle/devstack,pombredanne/devstack,thomasem/devstack,sequenceiq/devstack,mssumanth/devstack,r-mibu/devstack,costingalan/devstack,vsham20/devstack,dirkmueller/devstack,Millnert/contrail-devstack,neerja28/Devstack_GlusterFS,nawawi/openstack,bljgaurav/openstack-test,kplus/devstack-moonshot,nati/devstack_public,TwinkleChawla/devstack,virtualopensystems/devstack,liuquansheng47/devstack,JioCloud/devstack,Mahito/devstack,tianweizhang/devstack,CloudServer/devstack,parul24/devstack,nuxeh/devstack,atulpatil301/devstack,nttmcl/devstack_public,promptworks/devstack,samgoon/devstack,eharney/devstack,atulpatil301/devstack,williamthegrey/devstack,promptworks/devstack,tianweizhang/devstack,citrix-openstack-build/devstack,ykaneko/devstack,ewindisch/raspi-devstack,avvocatodemarchis/devstack,dtroyer/devstack,mc2014/devstack,yamt/devstack,Mahito/devstack,samgoon/devstack,sstrato/devstack,srics/devstack,upadhyay-prashant/devstack,nawawi/openstack,parul24/devstack,openstack-dev/devstack,mc2014/devstack,bswartz/devstack,wenhuizhang/devstack,pombredanne/devstack,liuquansheng47/devstack,eharney/devstack,herrsechs/devstack,inkerra/devstack,cloudbuilders/devstack,richliu/devstack,eshnil2000/devstack,prithivm/branch01,BSJAIN92/OpenStack,herrsechs/devstack,sc68cal/devstack,ozamiatin/devstack,bq-xiao/devstack,r-mibu/devstack,upadhyay-prashant/devstack,bswartz/devstack,kplus/devstack-moonshot,flavio-fernandes/devstack,costingalan/devstack,ozamiatin/devstack,savi-dev/devstack,cloudbuilders/devstack,group-policy/devstack,ewindisch/raspi-devstack,dtroyer/devstack,Juniper/devstack,dirkmueller/devstack,affo/devstack,NaokiMiyata/devstack,sequenceiq/devstack,andrewrothstein/devstack,bigswitch/devstack,BSJAIN92/OpenStack,Yuriy-Leonov/devstack,HPCHub/devstack,nuxeh/devstack,vsham20/devstack,armando-migliaccio/devstack,j4/devstack,mssumanth/devstack,CloudServer/devstack,innodee/openstackk,HPCHub/devstack,varunarya10/devstack,sc68cal/devstack,varunarya10/devstack,NaokiMiyata/devstack,CiscoSystems/devstack,savi-dev/devstack,vishnugonela/devstack,jamielennox/devstack,j4/devstack,richliu/devstack,shootstar/devstacktest,citrix-openstack-build/devstack,mmasaki/devstack,mmasaki/devstack,flavio-fernandes/devstack,prithivm/branch01,TwinkleChawla/devstack,openstack-dev/devstack,LoHChina/devstack,nttmcl/devstack_public,noironetworks/devstack,LoHChina/devstack,pacinete/devstack,bljgaurav/openstack-test,thomasem/devstack,olivierlemasle/devstack,pczerkas/devstack,affo/devstack,andrewrothstein/devstack,bigswitch/devstack,nati/devstack_public,rushiagr/devstack,pczerkas/devstack,noironetworks/devstack,bq-xiao/devstack,neerja28/Devstack_GlusterFS,avvocatodemarchis/devstack,ykaneko/devstack,pacinete/devstack,wenhuizhang/devstack,group-policy/devstack,vishnugonela/devstack,rushiagr/devstack